1. Field of the Invention
The invention relates to a barrier film encapsulating apparatus for insulating pipes, and more particularly, to a barrier film encapsulating apparatus for coaxially encapsulating the insulating pipes with micro-open cell foams.
2. Description of the Related Art
Typically, a cylindrical insulating pipe 7 manufactured by a extrusion die apparatus is coaxially coated by foaming as illustrated in FIG. 6. Since the wall 70 has a temperature differential from the raw material and extrusion die of the apparatus during the manufacturing process a sheath 71 (non-foaming layer) with a specific thickness is formed on a wall 70 of the insulating pipe 7. The sheath 71 has both an inner layer and an outer layer, and a micro-open cell foam material 72 for forming a chamber is encased between the inner and outer layers of the sheath 71. As long as the air in the chamber is withdrawn to vacuum, heat transfer thereof is minimized with better insulative effect to enhance functionality of the cylindrical insulating pipe 7. Similar insulating pipes whose temperatures are maintained via a micro-open cell foam material layer are disclosed in Taiwanese Patent Publication TW231746, TW263049, TW 439928, and TW 463903.
Since the micro-open cell foam material is a brittle polymeric material, the material is prone to leaking and wearing under a high vacuum environment (6-10 torr) within the chamber, thereby degrading its durability and adversely affecting the insulating effect of the insulating pipe. This creates conflicting scenarios in designing the outer layer of the insulating pipe, limiting such insulating pipe to be only adaptable to a low vacuum environment (1-2 torr) within the chamber.
Theoretically, a barrier film (also known as deposition film) may be encapsulated on the outer sheath of the insulating pipe. The deposition film is made of laminated layers of a polymeric plastic film and an anti-radiation aluminum film, wherein the number of the laminated layers depends on the actual need. With the protection and insulation of the deposition film supplemented with an anti-radiation function, effect of the vacuum suction process on the micro-open cell foam material is minimized, so as to improve its durability and insulation, solving conventional problems discussed above.
However, a major concern for the above method lies in the encapsulating process thereof. When the current insulating process is carried out by encapsulating the outer layer of the pipe with the insulating layer, ribbon-shaped insulating material is mostly encapsulated on the metallic or non-metallic pipe either by wrapping or metal adhesion. However, such encapsulating method does not yield a good sealing result even if silicon is further supplemented to fill any gap, making the entire process more complicated.
Furthermore, it is also difficult to apply the available conventional vacuum packing machines to the above encapsulating method. Since the current vacuum packing machine is designed to adapt the planar foam plate, the packing method involves disposing the foam plate in a deposition bag, followed by sucking out the air in the bag using a vacuum pump to achieve a vacuum pressure preset by the operator, and sealing by thermal compression to obtain the desired vacuum insulation panel. Apparently, it is difficult to apply this encapsulating mechanism on the insulating pipe as no match can be made for with the cross-section of the pipe for tightly encapsulating the outer circumference of the pipe, and no seal can be made by thermal compression.
Summarizing from the above, it is understood that neither the current pipe encapsulating method nor vacuum packing equipment is designed to adapt the insulation panel having micro-open cell foam material, and demands associated with encapsulating the pipe with the barrier film, sealing by thermal compression, and vacuum suction process are not satisfied as a result.
Therefore, it has been a present subject of the related research field to develop a barrier film encapsulating apparatus that achieves the desired insulation for the insulating pipes, adapts to a variety of pipes, and at the same time satisfies the requirement for mass production.